[简答题]Translate the following passages into Chinese.        It should be noted, however, that the existence of a letter of credit is not a guarantee of payment to anyone. Its existence only assures payment to the beneficiary if the terms and conditions of the letter of credit are fulfilled. In addition, a letter of credit does not insure that the materials purchased will be those invoiced or shipped. Banks issuing letters of credit deal in documents not in merchandise. They have no legal obligation to inspect the actual merchandise. The quality and quantity of the merchandise shipped, although specified in the documents submitted to the bank as required by the letter of credit terms, ultimately depends on the honesty and integrity of the seller who has manufactured, packaged, and arranged for shipment of the merchandise. If the buyer discovers that the merchandise has been mislabeled or the cartons are empty, he must sue the seller, not the bank.